ATC (Automatic Train Control) and ATP (Automatic Train Protection) used in railroad safety systems include a profiled train speed control apparatus which generates a braking instruction profile in accordance with a train-car performance ahead of a movement authority limit like a signal, and which automatically activates brakes when the speed exceeds such a profile to stop the train before the movement authority limit.
Information on the movement authority limit is transmitted to an on-train control apparatus through a track circuit, a beacon, and a wireless device, etc. The on-train control apparatus generates a braking instruction profile based on such information, the train-car performance and gradient information, etc.
In the case of a train, there is an idle running time of several seconds until actual deceleration starts after a braking instruction is output. Hence, the braking instruction profile must be generated in consideration of the idle running time. If such an idle run is out of consideration, the train may overrun the movement authority limit.
Patent Literature 1 discloses a train speed control apparatus which generates a train deceleration profile based on a gradient and the braking performance of a train, and uses a braking instruction profile that is a curvature shifted ahead from the deceleration profile by a running distance during an idle running time period based on a presumption that the train accelerates during the idle running time period in accordance with a railway track condition and a power-running instruction.
Note that power running means to transmit power to a driving device of a train, and when a power-running instruction is given, the train accelerates.